Heat dissipation module

ABSTRACT

A heat dissipation module includes a centrifugal fan and a heat pipe. The centrifugal fan includes at least one axial air inlet and a radial air outlet, wherein an air channel sidewall of the centrifugal fan has heat dissipation fins in an inner wall thereof. The heat pipe has a heat source contact section and a heat dissipation section, the heat dissipation section is in contact with an outer wall of the air channel sidewall, and the heat source contact section is in contact with a heat source.

RELATED APPLICATIONS

This application claims priority to Taiwan Application Serial Number101112477, filed Apr. 9, 2012, which is herein incorporated byreference.

BACKGROUND

1. Field of Invention

The present invention relates to a heat dissipation module. Moreparticularly, the present invention relates to a heat dissipation moduleequipped with a centrifugal fan.

2. Description of Related Art

FIG. 1 illustrates a perspective view of a conventional heat dissipationmodule equipped with a centrifugal fan. The heat dissipation moduleillustrated in FIG. 1 is used in most notebook computers as their systemcooler. A heat dissipation module 100 includes a centrifugal fan 102, aheat pipe 110 and a heat dissipation fin array 112. A heat sourcecontact section 110 a of the heat pipe 110 is used to connect with aheat source, e.g., a CPU while a heat dissipation section 110 b of theheat pipe 110 is used to connect with the heat dissipation fin array112, thereby transferring heat from the heat source contact section 110a to the heat dissipation section 110 b and the heat dissipation finarray 112. The heat dissipation section 110 b and the heat dissipationfin array 112 are fastened to an air outlet 102 a of the centrifugal fan102. When an impeller 108 of the centrifugal fan 102 rotates, airflowscarry the heat on the heat dissipation section 110 b and the heatdissipation fin array 112 out of the notebook computer.

However, the notebook computers are designed to be thin and compact, thedissipation modules inside them are also designed to be thinner. Hence,the heat dissipation section 110 b of the heat pipe 110 must have asmaller thickness, thereby affecting the heat pipe's heat dissipationperformance. In addition, when the dissipation module is designed to bethinner, its heat dissipation fin array 112 also needs a smallerthickness and the heat dissipation module's performance cannot beenhanced. Accelerating a rotation speed of the centrifugal fan 102 mayrise the heat dissipation performance, but also bring about the noises.For the forgoing reasons, there is a need for dealing the heatdissipation efficiency issue due to the thinner notebook computerdesign.

SUMMARY

It is therefore an objective of the present invention to provide animproved heat dissipation module equipped with a centrifugal fan.

In accordance with the foregoing and other objectives of the presentinvention, a heat dissipation module includes a centrifugal fan and aheat pipe. The centrifugal fan includes at least one axial air inlet andan radial air outlet, wherein an air channel sidewall of the centrifugalfan has heat dissipation fins in an inner wall thereof. The heat pipehas a heat source contact section and a heat dissipation section, theheat dissipation section is in contact with an outer wall of the airchannel sidewall, and the heat source contact section is in contact witha heat source.

According to another embodiment disclosed herein, the heat dissipationsection has a circular cross-section.

According to another embodiment disclosed herein, the air channelsidewall has a concave arc section in an outer wall thereof to be incontact with the heat dissipation section of the heat pipe.

According to another embodiment disclosed herein, the air channelsidewall is a metallic sidewall.

According to another embodiment disclosed herein, the centrifugal fanfurther includes an upper cover and a lower cover, the upper cover, thelower cover and the air channel sidewall collectively form a completehousing of the centrifugal fan.

According to another embodiment disclosed herein, the upper cover is ametal cover or a plastic cover.

According to another embodiment disclosed herein, the lower cover is ametal cover or a plastic cover.

According to another embodiment disclosed herein, a contact sectionbetween the heat dissipation section and an outer wall of the airchannel sidewall is greater than a half length of the air channelsidewall.

According to another embodiment disclosed herein, the heat dissipationfins have cutouts to collectively define an inner air channel of thecentrifugal fan.

According to another embodiment disclosed herein, the cutouts of theheat dissipation fins are V-shaped cutouts.

Thus, the heat dissipation module disclosed herein with its heat pipesecured to an outer wall of the air channel sidewall and air channelsidewall equipped with inner heat dissipation fins, thereby maintaininga heat pipe with a circular cross-section and not being overly flattenedand maintaining a full heat dissipation performance for the heat pipe.In addition, a heat dissipation fin array is removed from a radial airoutlet of the centrifugal fan in the heat dissipation module disclosedherein, the airflow volume is thus increased to enhance a totalconvection within a whole computer system.

It is to be understood that both the foregoing general description andthe following detailed description are by examples, and are intended toprovide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the invention, and are incorporated in and constitute apart of this specification. The drawings illustrate embodiments of theinvention and, together with the description, serve to explain theprinciples of the invention. In the drawings,

FIG. 1 illustrates a perspective view of a conventional heat dissipationmodule equipped with a centrifugal fan;

FIG. 2 illustrates a perspective view of a heat dissipation moduleequipped with a centrifugal fan according to an embodiment of thisinvention;

FIG. 3 illustrates a cross-sectional view taken along a cross-sectionline 3-3′ in FIG. 2;

FIG. 4 illustrates an exploded view of the heat dissipation module inFIG. 2;

FIG. 5 illustrates a schematic view of how a heat dissipation sidewallof a centrifugal fan being manufactured according to an embodiment ofthis invention;

FIG. 6 illustrates a cross-sectional view of a heat dissipation sidewallof a centrifugal fan according to another embodiment of this invention;and

FIG. 7 illustrates a cross-sectional view of a heat dissipation sidewallof a centrifugal fan according to still another embodiment of thisinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made in detail to the present preferredembodiments of the invention, examples of which are illustrated in theaccompanying drawings. Wherever possible, the same reference numbers areused in the drawings and the description to refer to the same or likeparts.

FIG. 2 illustrates a perspective view of a heat dissipation module 200equipped with a centrifugal fan according to an embodiment of thisinvention. In order to deal with the heat dissipation efficiency due tothe thinner heat dissipation module, the heat dissipation module 200 hasa heat dissipation section 210 b of a heat pipe 210 attached to an outerwall of an air channel sidewall 202. The air channel sidewall 202 isdesigned to have heat dissipation fins (see heat dissipation fins 202 billustrated in FIG. 3) in its inner walls to replace a conventionaldesign of the heat dissipation module, e.g., the heat dissipation module100 illustrated in FIG. 1.

In the new design of the heat dissipation module 200, the heat generatedfrom a heat source (not illustrated in the drawings) is transferred froma heat source contact section 210 of the heat pipe 210 to a heatdissipation section 210 b of the heat pipe 210, and further transferredfrom an outer wall of the air channel sidewall 202 to the heatdissipation fins at an inner wall of the air channel sidewall 202, andcarried out from a radial air outlet 201 a of the centrifugal fan 201 byairflows generated by a rotating impeller 208.

In this embodiment, a contact section between the heat dissipationsection 210 b of the heat pipe 210 and an outer wall of the air channelsidewall 202 is greater than a half length of the air channel sidewall202, that is, a contact area between the heat pipe 210 and the airchannel sidewall 202 is large enough to enhance the heat dissipation ofthe heat dissipation module 200.

FIG. 3 illustrates a cross-sectional view taken along a cross-sectionline 3-3′ in FIG. 2. In this embodiment, the heat dissipation section210 b of the heat pipe 210 has a circular cross-section (an exactcircular cross-section) to cause the heat pipe to have a full heatdissipation performance. However, the heat dissipation section 210 b isnot limited to a heat pipe with a circular cross-section, a heat pipewith a noncircular cross-section is also applicable. The air channelsidewall 202 has a concave arc section 202 a in an outer wall thereof tobe in contact with the heat dissipation section 210 b of the heat pipe210. The air channel sidewall 202 has heat dissipation fins 202 b in aninner wall thereof, and each heat dissipation fin 202 b has its cutout202 c. Thus, the heat dissipation fins 202 b have their cutouts 202 c tocollectively define an inner air channel of the centrifugal fan throughwhich airflows pass through and carry out heat. In this embodiment, thecutouts 202 c of the heat dissipation fins 202 b are, but not limitedto, V-shaped cutouts. The air channel sidewall 202 is made frommaterials with high thermal efficiencies. In this embodiment, the airchannel sidewall 202 is made from metallic materials. The upper cover206 or lower cover 204 of the centrifugal fan's housing can be made frommaterials with high thermal efficiencies, e.g., metallic materials.However, the upper cover 206 or lower cover 204 of the centrifugal fan'shousing is not limited to materials with high thermal efficiencies,e.g., the upper cover 206 or lower cover 204 of the centrifugal fan'shousing can be made from plastic materials. When the upper cover 206,the lower cover 204 and the air channel sidewall 202 are assembled, theheat can be further transferred from the air channel sidewall 202 to theupper cover 206 or the lower cover 204 to expand heat dissipation areas.That is, the upper cover 206 or the lower cover 204 shares the samefunction, i.e., expanding heat dissipation areas, with the heatdissipation fins 202 b.

FIG. 4 illustrates an exploded view of the heat dissipation module 200in FIG. 2 to detail the relationships between the components of the heatdissipation module 200. The upper cover 206 of the heat dissipationmodule 200 has an axial air inlet 206 a such that the air above thecentrifugal fan can be introduced into the centrifugal fan. The lowercover 204 of the heat dissipation module 200 has an axial air inlet 204a such that the air under the centrifugal fan can be introduced into thecentrifugal fan. The heat dissipation module 200 may need single oneaxial air inlet (204 a or 206 a), instead of two axial air inlets (204a, 206 a) at two opposite sides. The upper cover 206, the lower cover204 and the air channel sidewall 202 collectively form a completehousing of the centrifugal fan, which encloses an impeller 208 within.The heat dissipation section 210 b of the heat pipe 210 is secured to aconcave arc section 202 a in an outer wall of the air channel sidewall202.

FIG. 5 illustrates a schematic view of how a heat dissipation sidewallof a centrifugal fan being manufactured according to an embodiment ofthis invention. In this embodiment, the air channel sidewall 202 can bea metal member manufactured by separating an upper mold 220 a and alower mold 220 b vertically along the arrows in the drawings. Thismanufacturing way is different from a horizontal mold separating way inmanufacturing a conventional air channel sidewall.

FIG. 6 illustrates a cross-sectional view of a heat dissipation sidewall302 of a centrifugal fan according to another embodiment of thisinvention. The heat dissipation sidewall 302 has two air channelsidewalls (302 a, 302 b) combined to increase heat dissipation fins 302d and thus expand heat dissipation areas.

FIG. 7 illustrates a cross-sectional view of a heat dissipation sidewall302′ of a centrifugal fan according to still another embodiment of thisinvention. The heat dissipation sidewall 302′ has three air channelsidewalls (302 a, 302 b, 302 c) combined to increase heat dissipationfins 302 d and thus further expand heat dissipation areas (compared withFIG. 6). In other embodiments, the heat dissipation sidewall may havefour or more air channel sidewalls combined to increase heat dissipationfins 302 d and thus further expand even more heat dissipation areas.

A performance simulation is conducted both on the heat dissipationmodule of this invention (the embodiment as illustrated in FIG. 2) and aconventional heat dissipation module (the embodiment as illustrated inFIG. 1) with the same rotation speed centrifugal fan and a table belowlists the comparison results. According to the table below, the heatdissipation module of this invention is equipped with a better heatefficiency such that the heat source core temperature is lowered byabout 9° C. compared with the conventional heat dissipation module.Furthermore, the heat dissipation module of this invention removes aheat dissipation fin array at a radial air outlet of a conventional heatdissipation module such that the airflow volume is increased by about0.35 CFM to enhance a total convection within a whole computer system.

Conventional heat Heat dissipation module of dissipation module thisinvention (metal air (centrifugal fan with channel sidewall and metalplastic housing) upper and lower covers) Heat source 69.3° C. 60.2° C.core temp. Air outlet 1.28 CFM 1.63 CFM airflow volume

According to the above-discussed embodiments, the heat dissipationmodule disclosed herein with its heat pipe secured to an outer wall ofthe air channel sidewall and air channel sidewall equipped with innerheat dissipation fins, thereby maintaining a heat pipe with a circularcross-section and not being overly flattened and maintaining a full heatdissipation performance for the heat pipe. In addition, a heatdissipation fin array is removed from a radial air outlet of thecentrifugal fan in the heat dissipation module disclosed herein, theairflow volume is thus increased to enhance a total convection within awhole computer system.

It will be apparent to those skilled in the art that variousmodifications and variations can be made to the structure of the presentinvention without departing from the scope or spirit of the invention.In view of the foregoing, it is intended that the present inventioncover modifications and variations of this invention provided they fallwithin the scope of the following claims and their equivalents.

What is claimed is:
 1. A heat dissipation module comprising: acentrifugal fan comprising at least one axial air inlet and a radial airoutlet, wherein an air channel sidewall of the centrifugal fan has heatdissipation fins in an inner wall thereof; and a heat pipe comprising aheat source contact section and a heat dissipation section, wherein theheat dissipation section is in contact with an outer wall of the airchannel sidewall, and the heat source contact section is in contact witha heat source.
 2. The heat dissipation module of claim 1, wherein theheat dissipation section has a circular cross-section.
 3. The heatdissipation module of claim 2, wherein the air channel sidewall has aconcave arc section in an outer wall thereof to be in contact with theheat dissipation section of the heat pipe.
 4. The heat dissipationmodule of claim 1, wherein the air channel sidewall is a metallicsidewall.
 5. The heat dissipation module of claim 4, wherein thecentrifugal fan further comprises an upper cover and a lower cover, theupper cover, the lower cover and the air channel sidewall collectivelyform a complete housing of the centrifugal fan.
 6. The heat dissipationmodule of claim 5, wherein the upper cover is a metal cover or a plasticcover.
 7. The heat dissipation module of claim 5, wherein the lowercover is a metal cover or a plastic cover.
 8. The heat dissipationmodule of claim 1, wherein a contact section between the heatdissipation section and the outer wall of the air channel sidewall isgreater than a half length of the air channel sidewall.
 9. The heatdissipation module of claim 1, wherein the heat dissipation fins havecutouts to collectively define an inner air channel of the centrifugalfan.
 10. The heat dissipation module of claim 9, wherein the cutouts ofthe heat dissipation fins are V-shaped cutouts.